Fusion of Radarsat-2 polarimetric images for improved stereo-radargrammetric DEM

Abstract

The new full polarimetric modes of Radarsat-2 were evaluated for digital elevation model (DEM) generation using stereo-radargrammetry with Toutin's three-dimensional physical model. The fusion of the four polarimetric bands was thus addressed to improve the resulting DEMs. The stereo-radargrammetric DEMs were evaluated with 20 cm accuracy Lidar elevation data. Results on a test site north of Québec City, Canada showed a good accuracy: 5 m and 6–7 m (1σ) for the horizontal positioning and the elevation (on bare soils), respectively. However, the best results were obtained when the four polarimetric bands were fused with the restoration method and the second best results (around 5% worse) were obtained with the SPAN method (total power of the four intensity bands).